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    <meta charset="UTF-8" />
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    <title>Document</title>
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  <body>
    <script>
      var score = prompt("请输入您的成绩");
      if (score >= 90) {
        alert("真棒");
      } else if (score >= 80) {
        alert("也很棒了奥");
      } else if (score >= 70) {
        alert("要继续加油奥");
      } else if (score >= 60) {
        alert("危险");
      } else {
        alert("我看你是要回家了");
      }
    </script>
  </body>
</html>
